Signs and message display devices for displaying messages, warnings and other information are well known in the art. In particular, signs utilized for highway safety and construction related applications are in widespread use to advise motorists and others of temporary or emergency conditions along roadways and other locations. These signs are usually intended for relatively temporary placement at particular locations where repair or rebuilding of the roadway is taking place, or where other safety conditions arise. Such signs are preferably portable, so that they can easily be removed or relocated as the temporary traffic or other conditions change.
Highway and construction related signs intended for temporary use typically comprise a message panel bearing an appropriate warning or other message and a separate sign supporting base or stand for supporting and displaying the message panel. A sign holding device is used to support or hold the message panel relative to the sign supporting base. The message panels may be of the rigid type, constructed of a metal, a plywood, or the like, or may be of the flexible type, constructed of a fabric, a plastic, or other flexible material, and designed to roll up, fold or otherwise break down for transportation and storage when not in use. The use of flexible message panels has greatly increased in recent years due to their increased portability and simplified handling demands.
These flexible message panels typically include a more rigid frame, such as a frame having a plurality of frame members which extend from one edge of the message panel across to an opposing edge. In particular, the frame may consist of a pair of crossed, horizontal and vertical frame members or battens, which are usually made from a fiberglass or other similar material. The battens may be of various sizes, depending upon the size of the message panel, but the horizontal batten typically has a standard width of approximately 1.25 inches and a standard thickness of approximately 0.375 inches or less. The combination of the message panel and the frame are commonly referred to as the sign.
The signs may be of any shape such as diamond, square, rectangular, octagonal, triangular or circular, and may be of varying sizes, generally depending upon the distance from which the signs must generally be viewed. Regardless of the shape and size, each sign conventionally includes a vertical frame member or batten as previously described.
The sign supporting base upon which the sign is mounted is typically a standardized or conventional supporting base. These support bases are designed and constructed so that one person can readily move them from a truck or other supply vehicle to a particular location. Commonly, these support bases are collapsible or foldable such that they occupy less space when stored or handled. In this configuration, the support base may include a number of individual ground engaging legs to support a central base and which are foldable to reduce the overall storage and transportation space required.
A sign post or upright portion usually extends upwardly from the lower portion of the supporting base. This upright portion is used to actually support the sign. Alternatively, some sign supporting bases include a central base for attachment of a separate upright portion. The upright portions may be of various cross-sectional sizes, shapes and lengths. The most common cross-section is square, though other cross-sections, such as round, may occasionally be used. They are often telescopic in nature, being of different sizes at vertical locations.
A typical sign supporting base is disclosed in U.S. Pat. No. 5,611,509 to Kulp et al., issued Mar. 18, 1997, and expressly incorporated herein by reference. The present invention is adaptable to function in conjunction with any conventional sign supporting base, but is preferably used with a supporting base having a relatively short upright portion.
The attachment of the sign to the upright portion of the sign supporting base requires the use of a sign holder or other mounting bracket. Because of the multitude of different sign types and sizes, as well as the number of various different sign supporting bases, a unique sign holder is often required for each sign or alternatively, each sign supporting base.
In an effort to reduce the number of differing sign holders, adjustable sign holders have recently become available. These adjustable sign holders facilitate the adaptation of most any sign to a single type of sign supporting base. This reduces the number of components necessary at a particular location while increasing the available sign and message options. Several different types of these adjustable sign holders are currently available for use with flexible and roll-up signs.
For example, one prior art adjustable sign holder for use with flexible signs, comprises an integral one-piece unit having a square tube mounting portion which is adapted to slide over and be secured on the upright portion of the sign supporting base. Extending forwardly from the mounting portion is a sign receiving portion, comprising a pair of arms with slots for receiving the sign's horizontal frame member. A latching member in conjunction with a biasing spring is used to retain the horizontal batten which is inserted into the slots.
This adjustable sign holder functions adequately, but is awkward to manipulate and not very adaptable to different types of signs and sign supporting bases. The number of springs and pivoting elements are susceptible to failure and the loss of the otherwise secured sign. Furthermore, the sign receiving portion is also awkward and difficult to operate, requiring one to manually pivot the latching member rearwardly and hold it there, with one hand, against the spring bias, while using the other hand to manipulate the sign's horizontal batten into the two corresponding receiving slots. This difficulty is increased in windy or other adverse conditions. Other prior art sign holders have similar problems.
What is needed, therefore, is a universal sign holder for use with a wide variety of different signs, message display devices, and the like. Ideally, the universal sign holder will require little or no adjustments, should be easy to install and operate and should provide secure attachment to a conventional sign supporting base. The universal sign holder should also be inexpensive to manufacture. Furthermore, the universal sign holder should be simple and quick to install in the field, by one person, and should be capable of positively securing the sign in position, in any reasonable environmental condition.